Carbide Two/Double Flute Straight Router Bits CNC Carving Engraving Knife Tools Specifications Size:3.175*22 Solid Carbide Two Flutes Straight Bit suitable for hardwood Suitable for the fastest CNC router/CNC machining and traditional  Solid Carbide Two Flute Straight Bits Designed to provide high finishing performance. Also, it has longer useful life and durability. •Suggestion RPM: 12,000(min)~24,000(min) Suggestion Feed Range: 5,000(mm/min)~12,000(mm/min) •The above data of Speed & Feed are just for reference. The correct data depends on specific application. •Custom order is acceptable.